A proper, working, stable optimisation for sort {$b cmp $a}

[p5sagit/p5-mst-13.2.git] / pp_ctl.c

diff --git a/pp_ctl.c b/pp_ctl.c
index c5f802a..a9bc3e5 100644 (file)
--- a/pp_ctl.c
+++ b/pp_ctl.c
@@ -1,7 +1,7 @@
 /*    pp_ctl.c
  *
  *    Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
- *    2000, 2001, 2002, 2003, by Larry Wall and others
+ *    2000, 2001, 2002, 2003, 2004, by Larry Wall and others
  *
  *    You may distribute under the terms of either the GNU General Public
  *    License or the Artistic License, as specified in the README file.
@@ -187,10 +187,13 @@ PP(pp_substcont)
        {
            SV *targ = cx->sb_targ;
 
-           if (DO_UTF8(dstr) && !SvUTF8(targ))
-               sv_catpvn_utf8_upgrade(dstr, s, cx->sb_strend - s, nsv);
-           else
-               sv_catpvn(dstr, s, cx->sb_strend - s);
+           assert(cx->sb_strend >= s);
+           if(cx->sb_strend > s) {
+                if (DO_UTF8(dstr) && !SvUTF8(targ))
+                     sv_catpvn_utf8_upgrade(dstr, s, cx->sb_strend - s, nsv);
+                else
+                     sv_catpvn(dstr, s, cx->sb_strend - s);
+           }
            cx->sb_rxtainted |= RX_MATCH_TAINTED(rx);
 
 #ifdef PERL_COPY_ON_WRITE
@@ -939,8 +942,19 @@ PP(pp_mapwhile)
        }
        /* copy the new items down to the destination list */
        dst = PL_stack_base + (PL_markstack_ptr[-2] += items) - 1;
-       while (items-- > 0)
-           *dst-- = SvTEMP(TOPs) ? POPs : sv_mortalcopy(POPs);
+       if (gimme == G_ARRAY) {
+           while (items-- > 0)
+               *dst-- = SvTEMP(TOPs) ? POPs : sv_mortalcopy(POPs);
+       }
+       else { 
+           /* scalar context: we don't care about which values map returns
+            * (we use undef here). And so we certainly don't want to do mortal
+            * copies of meaningless values. */
+           while (items-- > 0) {
+               (void)POPs;
+               *dst-- = &PL_sv_undef;
+           }
+       }
     }
     LEAVE;                                     /* exit inner scope */
 
@@ -1047,8 +1061,9 @@ PP(pp_flip)
 #define RANGE_IS_NUMERIC(left,right) ( \
        SvNIOKp(left)  || (SvOK(left)  && !SvPOKp(left))  || \
        SvNIOKp(right) || (SvOK(right) && !SvPOKp(right)) || \
-       (looks_like_number(left) && SvPOKp(left) && *SvPVX(left) != '0' && \
-        looks_like_number(right)))
+       (((!SvOK(left) && SvOK(right)) || ((!SvOK(left) || \
+          looks_like_number(left)) && SvPOKp(left) && *SvPVX(left) != '0')) \
+         && (!SvOK(right) || looks_like_number(right))))
 
 PP(pp_flop)
 {
@@ -1056,9 +1071,9 @@ PP(pp_flop)
 
     if (GIMME == G_ARRAY) {
        dPOPPOPssrl;
-       register I32 i, j;
+       register IV i, j;
        register SV *sv;
-       I32 max;
+       IV max;
 
        if (SvGMAGICAL(left))
            mg_get(left);
@@ -1066,7 +1081,8 @@ PP(pp_flop)
            mg_get(right);
 
        if (RANGE_IS_NUMERIC(left,right)) {
-           if (SvNV(left) < IV_MIN || SvNV(right) > IV_MAX)
+           if ((SvOK(left) && SvNV(left) < IV_MIN) ||
+               (SvOK(right) && SvNV(right) > IV_MAX))
                DIE(aTHX_ "Range iterator outside integer range");
            i = SvIV(left);
            max = SvIV(right);
@@ -1779,15 +1795,20 @@ PP(pp_enteriter)
        cx->blk_loop.iterary = (AV*)SvREFCNT_inc(POPs);
        if (SvTYPE(cx->blk_loop.iterary) != SVt_PVAV) {
            dPOPss;
-           if (RANGE_IS_NUMERIC(sv,(SV*)cx->blk_loop.iterary)) {
-                if (SvNV(sv) < IV_MIN ||
-                    SvNV((SV*)cx->blk_loop.iterary) >= IV_MAX)
-                    DIE(aTHX_ "Range iterator outside integer range");
-                cx->blk_loop.iterix = SvIV(sv);
-                cx->blk_loop.itermax = SvIV((SV*)cx->blk_loop.iterary);
+           SV *right = (SV*)cx->blk_loop.iterary;
+           if (RANGE_IS_NUMERIC(sv,right)) {
+               if ((SvOK(sv) && SvNV(sv) < IV_MIN) ||
+                   (SvOK(right) && SvNV(right) >= IV_MAX))
+                   DIE(aTHX_ "Range iterator outside integer range");
+               cx->blk_loop.iterix = SvIV(sv);
+               cx->blk_loop.itermax = SvIV(right);
            }
-           else
+           else {
+               STRLEN n_a;
                cx->blk_loop.iterlval = newSVsv(sv);
+               (void) SvPV_force(cx->blk_loop.iterlval,n_a);
+               (void) SvPV(right,n_a);
+           }
        }
     }
     else {
@@ -2104,6 +2125,7 @@ PP(pp_redo)
     TOPBLOCK(cx);
     oldsave = PL_scopestack[PL_scopestack_ix - 1];
     LEAVE_SCOPE(oldsave);
+    FREETMPS;
     return cx->blk_loop.redo_op;
 }
 
@@ -2171,6 +2193,7 @@ PP(pp_goto)
     char *label;
     int do_dump = (PL_op->op_type == OP_DUMP);
     static char must_have_label[] = "goto must have label";
+    AV *oldav = Nullav;
 
     label = 0;
     if (PL_op->op_flags & OPf_STACKED) {
@@ -2231,7 +2254,7 @@ PP(pp_goto)
                GvAV(PL_defgv) = cx->blk_sub.savearray;
                /* abandon @_ if it got reified */
                if (AvREAL(av)) {
-                   (void)sv_2mortal((SV*)av);  /* delay until return */
+                   oldav = av; /* delay until return */
                    av = newAV();
                    av_extend(av, items-1);
                    AvFLAGS(av) = AVf_REIFY;
@@ -2257,6 +2280,9 @@ PP(pp_goto)
 
            /* Now do some callish stuff. */
            SAVETMPS;
+           /* For reified @_, delay freeing till return from new sub */
+           if (oldav)
+               SAVEFREESV((SV*)oldav);
            SAVEFREESV(cv); /* later, undo the 'avoid premature free' hack */
            if (CvXSUB(cv)) {
 #ifdef PERL_XSUB_OLDSTYLE
@@ -2306,7 +2332,7 @@ PP(pp_goto)
                else {
                    if (CvDEPTH(cv) == 100 && ckWARN(WARN_RECURSION))
                        sub_crush_depth(cv);
-                   pad_push(padlist, CvDEPTH(cv), cx->blk_sub.hasargs);
+                   pad_push(padlist, CvDEPTH(cv), 1);
                }
                PAD_SET_CUR(padlist, CvDEPTH(cv));
                if (cx->blk_sub.hasargs)
@@ -2714,7 +2740,6 @@ Perl_sv_compile_2op(pTHX_ SV *sv, OP** startop, char *code, PAD** padp)
 #else
     SAVEVPTR(PL_op);
 #endif
-    PL_hints &= HINT_UTF8;
 
     /* we get here either during compilation, or via pp_regcomp at runtime */
     runtime = IN_PERL_RUNTIME;
@@ -2756,7 +2781,7 @@ Locate the CV corresponding to the currently executing sub or eval.
 If db_seqp is non_null, skip CVs that are in the DB package and populate
 *db_seqp with the cop sequence number at the point that the DB:: code was
 entered. (allows debuggers to eval in the scope of the breakpoint rather
-than in in the scope of the debuger itself).
+than in in the scope of the debugger itself).
 
 =cut
 */